The utility model content
The purpose of this utility model is to provide a kind of lithium battery group that makes can farthest bring into play its superiority; increase the service life; lithium battery is monitored when the charge and discharge in real time; lithium battery intelligent charge-discharge system and the computer of balancing energy between overvoltage, overcurrent, temperature protection and battery are provided, thereby solve the foregoing problems that exists in the prior art.
To achieve these goals, the technical solution adopted in the utility model is as follows:
A kind of lithium battery intelligent charge-discharge system comprises master controller, charging control circuit, data acquisition circuit and equalizing circuit, and described charging control circuit, described data acquisition circuit and described equalizing circuit are connected with described master controller respectively.
Preferably, also comprise electric quantity metering module and storing communication module, described electric quantity metering module is connected with described master controller respectively with described storing communication module.
Preferably, described master controller is single-chip microcomputer.
Preferably, described data acquisition circuit comprises voltage collection circuit, current acquisition circuit and temperature collecting device.
Preferably, described temperature collecting device is the DS18B20 digital temperature sensor.
Preferably, described current acquisition circuit comprises the closed loop current transducer.
Preferably, described storing communication module comprises eeprom memory.
A kind of computer comprises described lithium battery intelligent charge-discharge system.
The beneficial effects of the utility model are:
The utility model is done real-time monitoring and protection at charging, the discharge of lithium battery group.Obtain battery information in real time, report to the police, stop filling, park at there being the problem charge status for example to make or processing such as forced shutdown.Prevent from overcharging the situation that causes the lithium battery group burning, explosion to occur; Make the lithium battery group can farthest bring into play its superiority, increase the service life, the lithium battery group is monitored when the charge and discharge in real time, balancing energy between overvoltage, overcurrent, temperature protection and each battery is provided.
Embodiment
In order to make the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with accompanying drawing, the utility model is further elaborated.Should be appreciated that embodiment described herein only in order to explaining the utility model, and be not used in restriction the utility model.
In order to make the lithium battery group can farthest bring into play its superiority, increase the service life, must monitor in real time when the charge and discharge lithium battery, balancing energy between overvoltage, overcurrent, temperature protection and battery is provided.Pass through master controller; overcharge except providing effectively when the charge and discharge battery pack, overcurrent, cross put, the temperature protection; can also realize the balancing energy between the single-unit lithium battery; the overall performance of battery pack is given full play to; and the data such as historical charge and discharge information of battery pack can be kept in the EEPROM, the power supply brain reads.Real-time monitoring and protection are done in charging, discharge at battery pack.The battery information that gets access to reports master controller, reports to the police, stops filling, parks at there being the problem charge status for example to make or processing such as forced shutdown.
As shown in Figure 1, the utility model discloses a kind of lithium battery intelligent charge-discharge system, comprise master controller, charging control circuit, data acquisition circuit and equalizing circuit, described charging control circuit, described data acquisition circuit and described equalizing circuit are connected with described master controller respectively.Also comprise electric quantity metering module and storing communication module, described electric quantity metering module is connected with described master controller respectively with described storing communication module.Described master controller is single-chip microcomputer.Described data acquisition circuit comprises voltage collection circuit, current acquisition circuit and temperature collecting device.Described temperature collecting device is the DS18B20 digital temperature sensor.Described current acquisition circuit comprises the closed loop current transducer.Described storing communication module comprises eeprom memory.
The invention also discloses a kind of computer of using described lithium battery intelligent charge-discharge system.
Whole system of the present utility model is master controller with the single-chip microcomputer, is to charge, discharging or at idle state whether over-current phenomenon avoidance is being arranged by gathering current information, judging battery pack, and its state is made respective handling.After each batteries voltage carried out collection analysis, determine that whether starting equalizing circuit carries out balancing energy to whole battery group, judged whether simultaneously to overcharge or crossed and put phenomenon.The collection of temperature is mainly used in the overheat protector of system.
Charging control circuit principle and realization:
Lithium battery normal charge method is undertaken by preliminary filling, constant current, constant voltage three phases, and sequential as shown in Figure 2.The utility model adopts the batch (-type) mise-a-la-masse method, as shown in Figure 3.The batch (-type) mise-a-la-masse method be preliminary filling and maintenance stage by opening and closing charge circuit off and on, needed little electric current when changing charging and hold mode equivalently, the performance requirement of the big electric current of needs when charging normal.
Voltage collection circuit principle and realization:
Lithium ion battery requires its terminal voltage control when charging below 4.2V, and for preventing from overcharging the damage battery, requirement must detect each single-unit lithium battery voltage in real time when charging.The utility model adopts voltage sample detection scheme shown in Figure 4.Its operation principle is: at first electronic switch K1, K2 upwards gets to the voltage detecting shelves, and passes through the multi-channel electronic switch Kn-1 of MCU (master controller) control, Kn-2 (n=1,2,3,4,5,6,7), synchronously electric capacity is received each single battery two ends respectively, made electric capacity charge to the voltage that capacitance voltage equals tested single battery; Disconnect the multi-channel electronic switch Kn-1 of MCU control then, Kn-2.K3 and the K4 access A/D converter that closes is simultaneously measured.
Equalizing circuit principle and design:
Notebook lithium battery group is the battery module that is composed in series by a plurality of single batteries, because the difference of bulk properties between the battery individuality, after several times discharged and recharged, battery pack can be unbalance, has a strong impact on efficient and the safety of battery pack.In addition, battery pack overcharging in charge and discharge process, overdischarge, electric current are excessive, temperature is crossed the difference that high phenomenon can be aggravated characteristic between battery, thereby cause the imbalance of characteristics such as capacity, voltage between the single-unit lithium battery, finally cause the rapid decline of battery pack overall permanence and the acceleration of part battery to damage.Therefore when being used in combination, lithium battery must solve the equilibrium problem of each single battery in battery pack.
The equilibrium of each batteries electric weight can be adopted multiple schemes such as resistance equilibrium, electric capacity equilibrium, transformer equilibrium in the battery pack.Because the utility model is at jumbo notebook lithium battery group, if adopt the resistance equilibrium, balancing speed is fast but will have too much energy and waste; Though the balanced not additionally power consumption of electric capacity, euqalizing current is generally less, is difficult to the equilibrium between the competent high-capacity lithium battery.So this equalizing circuit adopts the transformer equalization scheme of taking into account efficient and speed.In specific design, directly adopt the DC/DC switch power module.Because switch power module has advantages such as power consumption is little, efficient is high, volume is little, quality is light, it is directly used as balance module is a well selection.When concrete the use, judge whether that according to the magnitude of voltage of detected each single battery needs carry out balancing energy to battery pack.If need, closed balanced master switch K5, K switch 1, K2 get to balanced shelves downwards, with the integral energy of battery pack the minimum battery of voltage are carried out extra equalizing charge, up to the difference of each batteries magnitude of voltage within the system requirements scope.Schematic diagram as shown in Figure 4.
The current acquisition circuit is to the realization of current sample:
Electric current is the key parameter of battery capacity estimation, and is therefore all very high to the requirement of precision, antijamming capability and the linearity error of current sample.Adopt the closed loop current transducer in the utility model, this element has outstanding precision, good linearty and best reaction time.This current sensor can be converted to charging and discharging currents the voltage signal of 0V-5V, can record charging and discharging currents after 10 A/D converters delivering to single-chip microcomputer are changed, and certainty of measurement is 0.2A.Its characteristic working curve as shown in Figure 5.Be reference point voltage with V REF among the figure, be defaulted as 2.5V, IP is measured electric current.
Temperature collecting device is to the realization of temperature sampling:
That the temperature collecting device in the utility model adopts is the digital temperature sensor D S18B20 that U.S. DALLAS semiconductor company produces.It is single chip architecture, need not to add the digital quantity that A/D converter is exportable 9-12 position.Monobus lin protocol is adopted in communication, can finish by a data wire the various operations of D S18B20.Because each D S18B20 contains unique sequence code, make on every bus to connect a plurality of D S18B20 simultaneously, this just makes that D S18B20 line is simple, system's flexible design, be suitable for the multi-point temperature measurement system, particularly share temperature detection and the control system of formation with single-chip microcomputer.
The storing communication module is to the realization of data storing communication:
The utility model handle in the charging and discharging lithium battery process discharges and recharges information, voltage, charging and discharging currents, working temperature, battery electric quantity that comprises each batteries etc. writes in real time by sampling to be preserved in the EEPROM storage chip, and the master control IC that can be connected on the SMBUS reads.Used all modules are the entity hardware module in the utility model.
By adopting the disclosed technique scheme of the utility model, obtained following useful effect:
The utility model is done real-time monitoring and protection at charging, the discharge of lithium battery group.Obtain battery information in real time, report to the police, stop filling, park at there being the problem charge status for example to make or processing such as forced shutdown.Prevent from overcharging the situation that causes the lithium battery group burning, explosion to occur; Make the lithium battery group can farthest bring into play its superiority, increase the service life, the lithium battery group is monitored when the charge and discharge in real time, balancing energy between overvoltage, overcurrent, temperature protection and each battery is provided.
The above only is preferred implementation of the present utility model; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the utility model principle; can also make some improvements and modifications, these improvements and modifications also should be looked protection range of the present utility model.